BE1026401B1 - DEVICE FOR REGULATING THE TEMPERATURE IN A SPEAKER - Google Patents

Abstract

The invention relates to a device (1) capable of being placed in communication with an enclosure (2), the device comprising a first part (3) which includes a thermoelectric module (4), the module being configured to maintain the temperature at room temperature. interior of the enclosure (2) at a set value, and in which the device comprises a stabilization part above the thermoelectric module (4) comprising a motorized valve (20) which operates according to the temperature differential created by the thermoelectric module (4) and as a function of the temperature outside the device so as to maintain a stable temperature differential, independently of said temperature outside the device. A third part of the device disposed above the stabilization part, comprises a heat sink (46) and may comprise one or more additional thermoelectric modules (45) configured to recover part of the thermal energy discharged from the enclosure (2) in the case where the enclosure is refrigerated with respect to a higher temperature.

Description

DEVICE FOR REGULATING THE TEMPERATURE IN A SPEAKER

Technical Field [0001] The present invention relates to the field of temperature regulation by the use of at least one thermoelectric module.

State of the art [0002] Thermoelectric modules are well known in the state of the art. These modules use the Peltier effect or its opposite effect, the Seebeck effect. Regarding the Peltier effect, a heat flux is generated between two junctions of electrical conductors of different materials when an electric current flows through the junctions. Conversely and with regard to the Seebeck effect, when the two junctions are subjected to a temperature difference, a current is generated. In practice, the thermoelectric modules used in most applications include a series of junctions between p and n type semiconductor materials, arranged between two parallel surfaces, so as to create a cold surface and a hot surface when the module is traversed by an electric current. Likewise, when a module is subjected to an outside temperature difference, it will function as an electric current generator.

The efficiency of a thermoelectric module largely depends on the difference ΔΤ between the temperatures of the two surfaces of the module, hereinafter called the module temperature differential. The modules are mainly used in applications for which the temperature must be regulated in a particularly precise and reliable manner, such as for example for containers

BE2018 / 5424 used for the transport of organs to be transplanted, or for applications in which the vibrations generated by conventional refrigeration systems constitute a major drawback which must be eliminated. However, all of these applications are limited to indoor environments, for example a hospital building or a transport vehicle, where the temperature of the environment does not substantially influence the temperature differential.

In an environment with uncontrolled temperature, the use of such thermoelectric modules is more difficult, variations in the temperature of the environment running the risk of destabilizing the temperature differential between the two heat transfer transfer faces. a thermoelectric module. In several cases, the influence over time of the temperature of the environment on the temperature differential cannot be eliminated by simple isolation means and / or by simple regulation of the amount of current injected into such a module. thermoelectric, which makes the thermoelectric solution inapplicable in a large number of fields. Examples include the temporary storage of biological samples, such as blood samples, in deposit boxes installed in several places, often in places likely to be subject to significant temperature variations over time.

Summary of the invention The present invention aims to propose a device for controlling the temperature by exploiting known thermoelectric effects, but which does not suffer from the drawbacks described above. The basic characteristics of such a device are described in the appended claims.

The invention relates to a device capable of being placed in communication with an enclosure, the device comprising a first part which includes a thermoelectric module, the module being configured to maintain the temperature inside the enclosure at a value setpoint, and in which the device comprises a stabilization part above the thermoelectric module comprising a motorized valve which operates as a function of the temperature differential created by the thermoelectric module and as a function of the temperature outside the device, so as to maintain a stable temperature differential, independently of said outside temperature. A third part of the device disposed above the stabilization part, comprises a heat sink, and may include a

BE2018 / 5424 second thermoelectric module configured to recover part of the thermal energy discharged from the enclosure in the case where the enclosure is refrigerated with respect to a higher temperature.

Brief description of the figures [0007] Figure 1 shows a device according to the invention in 3D view.

FIG. 2 represents several plan and section views of the device in FIG. 1.

Figure 3 shows a view of the housing components which are part of the stabilization part of a device according to the invention.

Figure 4 is an illustration of the operation of the valve which is part of the stabilization part of a device according to the invention.

Figure 5 shows a detail of the device according to one embodiment of the invention.

Detailed description of an embodiment of the invention The device shown in the various figures is a device according to a preferred but non-limiting embodiment of the invention, the invention being limited only by the appended claims. The device 1 as shown in Figure 1 is arranged on an enclosure 2 in which the temperature must be maintained. The operation of the device will first be described on the basis of a current situation, according to which the interior of the enclosure 2 is maintained at a temperature below the temperature outside the device. For example, in a temporary storage box for biological samples, the temperature inside enclosure 2 may have to be maintained at a setpoint of 5 ° C, regardless of the outside temperature, which can vary between 10 ° and 30 ° over a 24 hour period.

The device comprises three parts, arranged successively in the vertical direction. At the bottom of the device is a first part 3, called the thermoelectric part, and which comprises a thermoelectric module 4 as it is known per se. In the preferred form of the device shown in the figures, a thermoelectric module 4 of the CPM-2F type is used, sold by the company CUI Inc. When it is powered by an electric current generated by a battery or by the network, the module 4 generates a temperature differential between the cold side A

BE2018 / 5424 of the module and the hot side B of the module. A fan 5 will distribute the air cooled by the module 4 in the enclosure 2 through an opening provided in a wall of the enclosure 2. The module 4 is arranged in a housing 6 with thermal insulation seals 7 disposed between the module 4 and the material of the housing 6. Below the thermoelectric module 4, between the cold face A and the fan 5, is a thermal transfer chamber 8.

The module 4 and the fan 5 are controlled by a first regulation loop which will activate the module and the fan to reach and maintain a set temperature in enclosure 2. The module 4 and the fan 5 operate in mode on / off as a function of a measurement of the temperature of the enclosure 2 by a temperature sensor placed in the enclosure and / or as a function of a measurement of the face A of the module by a sensor 36 mounted on said face AT.

According to the preferred embodiment, the chamber 8 comprises a wall 9 of conical or symmetrically curved shape (for example parabolic) whose top is oriented upwards, and provided with a central orifice 10. The wall 9 is fixed to the side walls of chamber 8 so as to be able to capture the condensation formed by the refrigeration effect, while allowing thermal transfer through the central orifice 10, when the module 4 is activated.

According to a preferred embodiment, the wall 9 is made of a thermally insulating material. When the module 4 is not activated, said wall 9 and the face A of said module 4 thus form an anteroom which voluntarily limits the heat transfers between the anteroom and the chamber 8 via the orifice 10 whose surface is strictly less than that of face A of module 4. This makes it possible to reduce the influence of temperature variations of enclosure 2 on face A of module 4 and improves the stability of the temperature difference between face A and B of module 4 .

Channels (not visible in the figures) are provided inside the housing to allow the evacuation of the condensation by the force of gravity towards a discharge nozzle 11.

According to a preferred embodiment, there is an evacuation space of for example about 0.5mm thick between the outer lateral faces of the thermoelectric module 4 and the walls of the housing cavity 6 in which the thermoelectric module is housed and the channel of the nozzle 11 is connected to the evacuation space. The whole of this internal channel is sealed up to the outlet of the nozzle 11 and forms a natural evacuation circuit of the condensation formed on the faces.

BE2018 / 5424 external lateral sides of the thermoelectric module 4. According to the same embodiment, said evacuation space, for example 0.5 mm thick, constitutes natural thermal insulation between the external lateral walls of the thermoelectric module 4 and the walls of the housing cavity 6 in which the thermoelectric module is housed. Said thermal insulation is achieved by the thermal resistance of the layer of air present in said evacuation space. According to the same embodiment, said evacuation space limits the contact surface between the external lateral walls of the thermoelectric module 4 and the walls of the cavity of the housing 6 to allow a single contact at the sealing points formed by the seals thermal insulation 7.

The thermal energy transferred from the cold face A to the hot face B of the thermoelectric module 4 must be removed to maintain the temperature differential at a stable level of around 30 ° C for example, regardless of the temperature at l outside the device. In the device of the invention, this evacuation is actively controlled using the second part of the device, called the stabilization part 15 and located above the thermoelectric part 3, a thermal insulation joint 16 being disposed between the thermoelectric part 3 and the stabilization part 15. The stabilization part 15 comprises a housing 17 which first comprises a second thermal transfer chamber 18 whose lower face largely corresponds with the hot face B of the thermoelectric module 4. The chamber 18 is thermally insulated from the chamber 8. This characteristic is achieved by the seals 7 and 16, and preferably also by the air space of for example 0.5 mm described above and by the use of a module 4 as shown in the figures, having a significant thickness between face A and face B. The fact of properly isolating the chambers 8 and 18 from one another will contribute to m important way to the stability of ΔΤ.

The chamber 18 includes a second fan 19 configured to accelerate the convection of hot air upwards. Above the second thermal transfer chamber 18 is arranged a motorized valve 20, controlled by an electric actuator 21 via a connecting rod 22. The components of the stabilization part 15 are shown in more detail in FIG. 3. The body 25 of the valve is a cylindrical element which is displaceable in the vertical direction by the actuation of the jack 21 which will pull or push the connecting rod. A series of pins is provided for assembling the actuator, the connecting rod and the valve body 25. The seat 26 of the valve is formed by an annular space inside the housing 17. The seat can be machined

BE2018 / 5424 in the housing or it may consist of a part fixed to the housing. The body 25 of the valve is connected to the first end of a piston 27 guided by a cylindrical orifice 28, the piston comprising a blocking element 29 at its second end which limits the movement of the body of the valve 25 in a vertical direction. The two housings 6 and 17 are formed from a material having a low thermal conductivity, and preferably also having a low electrical conductivity. According to a preferred embodiment, these materials are thermoplastics with an amorphous and / or thermosetting structure thanks to their high mechanical strength in the face of concentrated temperatures and on the other hand thanks to their low thermal conductivity compared to thermally conductive materials such as l 'steel.

Figure 4 shows the positions ‘open valve 'and‘ closed valve' of the device. When the valve 20 is raised (open position) (FIG. 4a), still in the case where the set temperature is lower than the temperature outside the device, the hot air can move towards the top of the device, by one or more eccentric orifices 35 provided in the housing 17 of the stabilization part 15. In the closed position of the valve 20 (see FIG. 4b), the air convection path is blocked. The operation of the valve 20, preferably synchronized with the operation of the fan 19 is automatically adjusted on the basis of the direct measurement of the temperature differential by two temperature sensors 36 and 37 arranged respectively on the cold side A and the hot side B of the thermoelectric module

4.r.

The valve 20 is controlled by a second regulation loop, which actuates the opening of the valve when the ΔΤ measured by the sensors 36 and 37 exceeds a set value, for example 30 ° C. The second regulation loop can be a PI loop or any other loop known in the state of the art (P, I, PID, etc.). The regulation is preferably based on a range of values around the set value or a percentage of the set value. At the start of operation of the device, the valve 20 is closed. Module 4 and the fan are activated, which leads to a decrease in temperature of the cold face A and an increase in temperature of the hot face B. When the hot face B of the module exceeds a value or a range of values relative to the cold face A, defined such that this excess leads to a situation of excessive differential ΔΤ, the valve opens and the fan 19 is activated, preferably at a fixed and predefined speed, thus creating a flow of hot air towards the top of the device. Other operating modes

BE2018 / 5424 could provide for a change in fan speed 19 depending on the difference between the measured. \ T and the set value for this. \ T. When the. \ T enters an acceptable value range, the valve 20 closes.

Above the stabilization part 15 is finally a third part 40, called the dissipation part of the device. Preferably, the dissipation part is located inside a cover 41 which surrounds the housing 17 of the stabilization part 15 and which is fixed to the housing 6 of the thermoelectric part 3 by screws and / or systems clips. The dissipation part 40 comprises a third thermal transfer chamber 42 comprising a lower portion in direct communication with the eccentric orifices 35 and the cylindrical orifice 28 towards the second thermal transfer chamber 18, and an upper portion which forms the internal space of a part 43 called a heat concentrator which has the shape of a cup partially encapsulated by the material of the cover 41. The concentrator 43 is preferably made of a highly thermal conductive material such as copper. The concentrator 43 is open at the bottom and closed at the top. As visible in FIG. 5, the ceiling of the third heat transfer chamber 42 is formed by the bottom 75 of the cup of the concentrator. The thickness of the bottom 75 is less than the thickness of the side walls 76 of the concentrator. This structure results in a functionality of the concentrator which is advantageous in terms of the evacuation of heat from the chamber 42. The heat evacuated from the second chamber 18 when the valve 20 is open, must then be evacuated quickly to the outside to ensure the stability of the. \ T on the module 4. The concentrator 43 will stimulate this transfer of thermal energy by rapid heating of the bottom 75 of the concentrator. In addition, this bottom is in thermoconductive contact with a second thermoelectric module 45. Preferably, the contact between these components is made even more thermoconductive by the application of a thermal paste between the upper face of the bottom 75 and the lower face of the module 45. Above module 45 and in thermal contact with the latter, the device further comprises a dissipator 46, comprising a base 80 and a row of strips 81 (see FIG. 5). This heatsink structure is known and it is not limiting. Other known heatsink structures can be used.

The second module 45 can operate as an electric current generator by exploiting the Seebeck effect, thanks to the gradual increase in temperature in the chamber 42 and thanks to the temperature difference between the

BE2018 / 5424 underside of module 45 being in contact with the concentrator 43 and the upper face of said module 45 being in contact with the dissipator 46. For this purpose, the second module 45 is connected for example to a rechargeable battery (not shown) which contributes to the supply of the first module 4 and / or other electrical components integrated into the device.

A temperature sensor 47 is arranged on the underside of the second module 45. A second temperature sensor (not shown) is housed in the base 80 of the dissipator 46, so as to measure the temperature on the other side of module 45, iede so as to measure the. \ T on said module 45. A third regulation loop is provided to regulate the operation of module 45: when the. \ T exceeds a threshold, the module will be connected to a rechargeable battery .

According to another embodiment, the dissipation part 40 does not include the second module 45, but it includes the dissipator 46. In this case, there is a direct thermoconductive contact between the bottom 75 of the concentrator 43 and the base of the heatsink 46.

In another form, the device does not include the concentrator 43, but the chamber 42 is entirely surrounded laterally by the non-thermally conductive material of the cover 41. The heat transfer in this case is carried out entirely by air convection in the chamber 42 and by thermal conduction in the base 80 and the lamellae 81 (or equivalent) of the dissipator 46. It is clear that the evacuation of heat in this case will be less effective, but this defect could be compensated by an adapted dimensioning chamber 42 and / or the dissipator 46. The device is preferably provided with a number of vents 44 in the second heat transfer chamber 42. These are openings to the outside of the device, at reduced section which are provided in the side wall of the concentrator 43 in the embodiment shown in the figures. The presence of the vents 44 performs a depressurization of the chamber 42 when the pressure in this chamber reaches an excessive level, so as to maintain the pressure in this chamber at an acceptable level. Preferably, pressure sensors are also provided: a first sensor can be mounted at the sensor 47 (or this sensor can be a temperature and pressure sensor). A second pressure sensor can be mounted between the fins of the dissipator 46. These sensors make it possible to monitor the pressure difference between the chamber 42 and the environment.

BE2018 / 5424 Furthermore, the device is provided with channels and / or openings for the passage of electric cables 50 necessary to supply the various components of the device 1.

The device 1 is also provided with a control unit, or alternatively, the device is connected to a control unit which is located outside the device, the unit being configured to acquire signals representing temperatures and - if applicable - pressures measured by the various sensors. The control unit also makes it possible to generate control signals according to the measured values. The different regulatory loops described above are therefore implemented through this control unit. The precise realization in terms of electrical and electronic components of the control unit is not described in detail here since this realization falls within the skills of a person skilled in the art in the field of air conditioning.

According to one embodiment, said control unit is provided with radio frequency communication means (example: RFID), for example for the identification and access management of biological samples stored in the pregnant 2.

Said control unit can also be provided with a preferably wireless telecommunication module (example: 3G / 4G / 5G) to allow connection and transmission of information relating to temperature regulation, states of operation of the device 1 and of said control unit, to at least one user interface and to at least one data computer server via a cloud computing system.

Instead of providing a single thermoelectric module 45 in the dissipation part 40 of the device, several modules 45 can be provided, for example positioned in a single plane. In this case, a concentrator 43 can be envisaged with the bottom 75 projecting from the periphery of the side walls 76. The bottom thus becomes a platform on which several (rows of) modules 45 are mounted. The multiplication of modules 45 increases the capacity of the device to recover thermal energy in the form of electric current.

Preferably, the device does not only work in the refrigeration regime but it can also heat the enclosure 2 to maintain the set temperature in the enclosure when the outside temperature drops below a certain level. For this purpose, the device is configured to reverse the polarity of

BE2018 / 5424 the power supply of module 4, when necessary. For example, we can have a scenario in which the outside temperature gradually drops from a level of 35 ° C to a level of -10 ° C in 2 or 3 hours while the temperature in enclosure 2 must be maintained at + 5 ° C.

At the beginning of this period, the temperature in the chamber 18 will be maintained at around 35 ° C, to ensure a temperature of about 30 ° C on the module 4. When the temperature drops, this holding at 35 ° C in the chamber 18 will be ensured by regulating the valve 20 and the fan 19 as described above. At one point, the temperature outside the device has become so low that the temperature in the chamber 18 begins to decrease, with the result that the temperature in the enclosure 2 drops below the set value. As soon as this temperature (detected for example via sensor 36) drops below a predefined value (eg below a range around the set value), the polarity of module 4 will be reversed and module 4 will start to heat the enclosure. A. \ T on the module 4 can again be maintained in heating mode, by the action of the valve 20.

The three parts 3.15 and 40 of the device are described above as being one above the other. It should be noted that this order is applicable to the operating position of the device, i.e. the position of the device when it is operational and mounted on an enclosure 2.

Claims (11)

claims I. Device (1) for regulating the temperature in an essentially closed enclosure (2), said device comprising three parts: a first part (3) capable of being placed in communication with the enclosure (2), the first part (3) comprising: - a first thermoelectric module (4) having a first face (A) and a second face (B), the first module being configured to be supplied by an electrical power source which is part of the device (1) or which is the exterior of the device (1), - a first thermal transfer chamber (8) in contact with said first face (A), - a fan (5) for distributing air conditioning through the first face (A) of said first module (4) in the enclosure (2), - temperature sensors (36,37) arranged on the two faces (A, B) of said first module (4), a second part (15) disposed above the first part (3) in the operating position of the device , said second part comprising a housing (17) which comprises a second thermal transfer chamber (18) in contact with the second face (B) of the first thermoelectric module (4), the second chamber (18) being separated by thermal insulation the first thermal transfer chamber (8), a third part (40) disposed above the second part (15) in the operating position of the device, said third part comprising a third thermal transfer chamber (42), and in which : • the second part (15) further comprises: a motorized valve (20) configured to regulate the convection of air between said second thermal transfer chamber (18) and the third thermal transfer chamber (42), a second fan (19) for forcing an air flow between said second chamber (18) and said third chamber (42), when the valve (20) is open, BE2018 / 5424 the valve (20) and the second fan (19) being connected to a control unit which regulates the operation of the valve (20) and the second fan (19) according to the temperatures measured by the temperature sensors ( 36,37), • the third part (40) further comprises a heat sink (46) disposed above said third heat transfer chamber (42) in the operating position of the device. 2. The device according to claim 1, further comprising one or more additional thermoelectric modules (45) arranged between the third heat transfer chamber (42) and the heat sink (46), the additional module (s) (45) being configured to charge a (re) chargeable source of electrical power. 3. The device according to any one of the preceding claims, in which the valve (20) comprises a body (25), a jack (21), a seat (26) fixed to or incorporated in the housing (17), and in which the valve body is a cylindrical element (25) configured to be actuated vertically by the jack (21), between an open position in which the valve allows the passage of an air flow between the second ( 18) and the third (42) heat transfer chamber, and a closed position in which the body (25) of the valve is in contact with the seat (26) of the valve, so as to block the passage of a flow air between said second and third heat transfer chambers (18, 42). 4. The device according to claim 3, in which the body (25) of the valve is connected to one of the ends of a piston (27), the piston being configured to move up or down (in the operating position of the device. ) relative to an orifice (28) which is incorporated in the housing (17), the piston comprising at its second end a blocking element (29) configured to limit the path of the body (25) of the valve in a vertical direction. 5. The device according to any one of the preceding claims, in which the first heat transfer chamber (8) comprises BE2018 / 5424 a wall (9) of conical shape or curved symmetrically, the top of said surface being oriented upwards (in the operating position of the device), an orifice (10) being provided in the middle of said conical wall or curved (9), the surface being connected to the side walls of said first chamber (8) so that the conical or curved wall (9) can collect water formed by condensation. 6. The device according to claim 5, wherein the conical or curved wall is formed from a thermal insulating material. 7. The device according to any one of the preceding claims, in which the third heat transfer chamber (42) is provided with depressurization vents (44). 8. The device according to any one of the preceding claims, in which the first part (3) comprises a housing (6), in which the first thermoelectric module (4) is provided with one or more thermal insulation seals (7) between the housing (6) and the first module (4). 9. The device according to claim 8, in which the device comprises a cover (41) which surrounds the housing (17) of the second part (15) and which is fixed to the housing (6) of the first part (3), the cover also comprising in its interior at least a portion of the third heat transfer chamber (42). 10. The device according to any one of the preceding claims, in which an upper part (in the operating position of the device) of the third heat transfer chamber (42) is formed by an element made of material of high thermal conductivity, said element having the shape of a cup which is open downwards, the bottom (75) of the cup forming the ceiling of the third chamber (42), and in which the thickness of the bottom of the cup is less than the thickness side walls (76) of the cup, and in which said bottom (75) is in thermoconductive contact with the dissipator BE2018 / 5424 (46), or - if necessary - with the additional thermoelectric module (s) (45). 11. The device according to any one of claims 5 above, provided with means for reversing the polarity of the supply of the first thermoelectric module (4).